Semiconductor Device and Method of Forming an Interposer Package with Through Silicon Vias

ABSTRACT

A semiconductor device has a carrier for supporting the semiconductor device. A first semiconductor die is mounted over the carrier. A first dummy die having a first through-silicon via (TSV) is mounted over the carrier. The first semiconductor die and the first dummy die are encapsulated using a wafer molding material. The carrier is removed. A first redistribution layer (RDL) is formed over a first surface of the first semiconductor die and a first surface of the first dummy die to electrically connect the first TSV and a contact pad of the first semiconductor die. An insulation layer is formed over the first RDL. A second RDL is formed over a second surface of the first dummy die opposite the first surface of the first dummy die and electrically connected to the first TSV. A semiconductor package is connected to the second RDL.

CLAIM OF DOMESTIC PRIORITY

The present application is a continuation of U.S. patent applicationSer. No. 12/325,587, filed Dec. 1, 2008, and claims priority to theforegoing parent application pursuant to 35 U.S.C. §120.

FIELD OF THE INVENTION

The present invention relates in general to semiconductor devices and,more particularly, to a semiconductor device providing an interposerpackage having through-silicon vias.

BACKGROUND OF THE INVENTION

Semiconductor devices are commonly found in modern electronic products.Semiconductor devices vary in the number and density of electricalcomponents. Discrete semiconductor devices generally contain one type ofelectrical component, e.g., light emitting diode (LED), transistor,resistor, capacitor, inductor, and power metal oxide semiconductor fieldeffect transistor (MOSFET). Integrated semiconductor devices typicallycontain hundreds to millions of electrical components. Examples ofintegrated semiconductor devices include microcontrollers,microprocessors, charged-coupled devices (CCDs), solar cells, anddigital micro-mirror devices (DMDs).

Semiconductor devices perform a wide range of functions such ashigh-speed calculations, transmitting and receiving electromagneticsignals, controlling electronic devices, transforming sunlight toelectricity, and creating visual projections for television displays.Semiconductor devices are found in the fields of entertainment,communications, power generation, networks, computers, and consumerproducts. Semiconductor devices are also found in electronic productsincluding military, aviation, automotive, industrial controllers, andoffice equipment.

Semiconductor devices exploit the electrical properties of semiconductormaterials. The atomic structure of semiconductor material allows itselectrical conductivity to be manipulated by the application of anelectric field or through the process of doping. Doping introducesimpurities into the semiconductor material to manipulate and control theconductivity of the semiconductor device.

A semiconductor device contains active and passive electricalstructures. Active structures, including transistors, control the flowof electrical current. By varying levels of doping and application of anelectric field, the transistor either promotes or restricts the flow ofelectrical current. Passive structures, including resistors, diodes, andinductors, create a relationship between voltage and current necessaryto perform a variety of electrical functions. The passive and activestructures are electrically connected to form logic circuits, whichenable the semiconductor device to perform high-speed calculations andother useful functions.

Semiconductor devices are generally manufactured using two complexmanufacturing processes, i.e., front-end manufacturing, and back-endmanufacturing, each involving potentially hundreds of steps. Front-endmanufacturing involves the formation of a plurality of die on thesurface of a semiconductor wafer. Each die is typically identical andcontains circuits formed by electrically connecting active and passivecomponents. Back-end manufacturing involves singulating individual diefrom the finished wafer and packaging the die to provide structuralsupport and environmental isolation.

One goal of semiconductor manufacturing is to produce smallersemiconductor devices. Smaller devices typically consume less power,have higher performance, and can be produced more efficiently. Inaddition, smaller semiconductor devices have a smaller footprint, whichis desirable for smaller end products. A smaller die size may beachieved by improvements in the front-end process resulting in die withsmaller, higher density active and passive components. Back-endprocesses may result in semiconductor device packages with a smallerfootprint by improvements in electrical interconnection and packagingmaterials.

In many applications, it is desirable to manufacture packages thatcombine several semiconductor dies into a single stacked package. Often,the dies are combined by the use of through-silicon vias (TSVs) whichprovide a conductive pathway to form the necessary electricalinterconnections between each of the semiconductor dies. The manufactureof TSVs, however, requires additional expensive and complicatedfabrication technologies. Often the TSVs are difficult to align as aresult of warpage of the components. Also, conventional TSVs can only betested after the via is formed and the semiconductor die is mounted tothe package. As a result, the use of conventional TSVs in stackedpackages increases the manufacturing cost of the package, and minimizesyield of the manufacturing process.

SUMMARY OF THE INVENTION

In one embodiment, the present invention is a method of making asemiconductor device including the steps of providing a carrier forsupporting the semiconductor device, mounting a first semiconductor dieover the carrier, mounting a first dummy die having a first TSV over thecarrier, encapsulating the first semiconductor die and the first dummydie using a wafer molding material, and removing the carrier. The methodfurther includes the steps of forming a first redistribution layer (RDL)over a first surface of the first semiconductor die and a first surfaceof the first dummy die to electrically connect the first TSV and acontact pad of the first semiconductor die. The method further includesthe steps of forming an insulation layer over the first RDL, forming asecond RDL over a second surface of the first dummy die opposite thefirst surface of the first dummy die and electrically connected to thefirst TSV, and connecting a semiconductor package to the second RDL.

In another embodiment, the present invention is a method of making asemiconductor device including the steps of providing a temporarycarrier, mounting a first semiconductor die over the temporary carrier,and mounting a first dummy die having a first TSV over the temporarycarrier. The method further includes the steps of depositing encapsulantover the first semiconductor die and the first dummy die, forming afirst conductive layer electrically connected to the first semiconductordie and TSV, and forming a second conductive layer electricallyconnected to the TSV.

In another embodiment, the present invention is a method of making asemiconductor device including the steps of providing a carrier,mounting a first semiconductor die over the carrier, mounting a secondsemiconductor die including a conductive via over the carrier, forming afirst conductive layer connected to the first semiconductor die and theconductive via, and forming a second conductive layer connected to theconductive via.

In another embodiment, the present invention is a semiconductor deviceincluding a first semiconductor die, a first dummy die including a TSVthat has a first surface coplanar with a first surface of the firstsemiconductor die, and encapsulant deposited over the firstsemiconductor die and the first dummy die. The device further includes afirst conductive layer formed over the first surface of the firstsemiconductor die and the first surface of the TSV to electricallyconnect the first semiconductor die and the TSV, and a second conductivelayer connected to a second surface of the TSV opposite the firstsurface of the TSV.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a printed circuit board (PCB) with different types ofpackages mounted to its surface;

FIGS. 2 a-2 c illustrate further detail of the representativesemiconductor packages mounted to the PCB;

FIGS. 3 a-3 g illustrate a method of forming a semiconductor deviceproviding a three-dimensional (3D) interposer package having a pluralityof TSV die;

FIG. 4 illustrates a top view of a wafer having a plurality of dummydies having TSVs for use in the semiconductor device of FIGS. 3 a-3 g;

FIGS. 5 a-5 g illustrate a method of forming a semiconductor deviceproviding a 3D interposer package having a plurality of TSV die, an RDLstructure is formed over both sides of the substrate;

FIGS. 6 a-6 g illustrate a method of forming a semiconductor deviceproviding a 3D interposer package having a plurality of TSV die, a dieis flip-chip mounted to the semiconductor device;

FIG. 7 illustrates a semiconductor device providing a 3D interposerpackage having a plurality of TSV die, a die is flip-chip mounted to thesemiconductor device using an underfill material;

FIGS. 8 a-8 i illustrate a method of forming a semiconductor deviceproviding a 3D interposer package having stacked TSV die, a die isflip-chip mounted to the semiconductor device; and

FIGS. 9 a-9 i illustrate a method of forming a semiconductor deviceproviding a 3D interposer package having stacked TSV die, asemiconductor package is mounted to the semiconductor device.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention is described in one or more embodiments in thefollowing description with reference to the Figures, in which likenumerals represent the same or similar elements. While the invention isdescribed in terms of the best mode for achieving the invention'sobjectives, it will be appreciated by those skilled in the art that itis intended to cover alternatives, modifications, and equivalents as maybe included within the spirit and scope of the invention as defined bythe appended claims and their equivalents as supported by the followingdisclosure and drawings.

Semiconductor devices are generally manufactured using two complexmanufacturing processes: front-end manufacturing and back-endmanufacturing. Front-end manufacturing involves the formation of aplurality of die on the surface of a semiconductor wafer. Each die onthe wafer contains active and passive electrical components which areelectrically connected to form functional electrical circuits. Activeelectrical components, such as transistors, have the ability to controlthe flow of electrical current. Passive electrical components, such ascapacitors, inductors, resistors, and transformers, create arelationship between voltage and current necessary to perform electricalcircuit functions.

Passive and active components are formed on the surface of thesemiconductor wafer by a series of process steps including doping,deposition, photolithography, etching, and planarization. Dopingintroduces impurities into the semiconductor material by techniques suchas ion implantation or thermal diffusion. The doping process modifiesthe electrical conductivity of semiconductor material in active devices,transforming the semiconductor material into a permanent insulator,permanent conductor, or changing the way the semiconductor materialchanges in conductivity in response to an electric field. Transistorscontain regions of varying types and degrees of doping arranged asnecessary to enable the transistor to promote or restrict the flow ofelectrical current upon the application of an electric field.

Active and passive components are formed by layers of materials withdifferent electrical properties. The layers can be formed by a varietyof deposition techniques determined in part by the type of materialbeing deposited. For example, thin film deposition may involve chemicalvapor deposition (CVD), physical vapor deposition (PVD), electrolyticplating, and electroless plating processes. Each layer is generallypatterned to form portions of active components, passive components, orelectrical connections between components.

The layers can be patterned using photolithography, which involves thedeposition of light sensitive material, e.g., photoresist, over thelayer to be patterned. A pattern is transferred from a photomask to thephotoresist using light. The portion of the photoresist patternsubjected to light is removed using a solvent, exposing portions of theunderlying layer to be patterned. The remainder of the photoresist isremoved, leaving behind a patterned layer. Alternatively, some types ofmaterials are patterned by directly depositing the material into theareas or voids formed by a previous deposition/etch process usingtechniques such as electroless and electrolytic plating.

Depositing a thin film of material over an existing pattern canexaggerate the underlying pattern and create a non-uniformly flatsurface. A uniformly flat surface is required to produce smaller andmore densely packed active and passive components. Planarization can beused to remove material from the surface of the wafer and produce auniformly flat surface. Planarization involves polishing the surface ofthe wafer with a polishing pad. An abrasive material and corrosivechemical are added to the surface of the wafer during polishing. Thecombined mechanical action of the abrasive and corrosive action of thechemical removes any irregular topography, resulting in a uniformly flatsurface.

Back-end manufacturing refers to cutting or singulating the finishedwafer into the individual die and then packaging the die for structuralsupport and environmental isolation. To singulate the die, the wafer isscored and broken along non-functional regions of the wafer called sawstreets or scribes. The wafer is singulated using a laser cutting deviceor saw blade. After singulation, the individual die are mounted to apackage substrate that includes pins or contact pads for interconnectionwith other system components. Contact pads formed over the semiconductordie are then connected to contact pads within the package. Theelectrical connections can be made with solder bumps, stud bumps,conductive paste, or wirebonds. An encapsulant or other molding materialis deposited over the package to provide physical support and electricalisolation. The finished package is then inserted into an electricalsystem and the functionality of the semiconductor device is madeavailable to the other system components.

FIG. 1 illustrates electronic device 10 having a chip carrier substrateor printed circuit board (PCB) 12 with a plurality of semiconductorpackages mounted on its surface. Electronic device 10 may have one typeof semiconductor package, or multiple types of semiconductor packages,depending on the application. The different types of semiconductorpackages are shown in FIG. 1 for purposes of illustration.

Electronic device 10 may be a stand-alone system that uses thesemiconductor packages to perform an electrical function. Alternatively,electronic device 10 may be a subcomponent of a larger system. Forexample, electronic device 10 may be a graphics card, network interfacecard, or other signal processing card that can be inserted into acomputer. The semiconductor package can include microprocessors,memories, application specific integrated circuits (ASICs), logiccircuits, analog circuits, RF circuits, discrete devices, or othersemiconductor die or electrical components.

In FIG. 1, PCB 12 provides a general substrate for structural supportand electrical interconnect of the semiconductor packages mounted on thePCB. Conductive signal traces 14 are formed on a surface or withinlayers of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess. Signal traces 14 provide for electrical communication betweeneach of the semiconductor packages, mounted components, and otherexternal system components. Traces 14 also provide power and groundconnections to each of the semiconductor packages.

In some embodiments, a semiconductor device has two packaging levels.First level packaging is the technique for mechanically and electricallyattaching the semiconductor die to a carrier. Second level packaginginvolves mechanically and electrically attaching the carrier to the PCB.In other embodiments, a semiconductor device may only have the firstlevel packaging where the die is mechanically and electrically mounteddirectly to the PCB.

For the purpose of illustration, several types of first level packaging,including wire bond package 16 and flip chip 18, are shown on PCB 12.Additionally, several types of second level packaging, including ballgrid array (BGA) 20, bump chip carrier (BCC) 22, dual in-line package(DIP) 24, land grid array (LGA) 26, multi-chip module (MCM) 28, quadflat non-leaded package (QFN) 30, and quad flat package 32, are shownmounted on PCB 12. Depending upon the system requirements, anycombination of semiconductor packages, configured with any combinationof first and second level packaging styles, as well as other electroniccomponents, can be connected to PCB 12. In some embodiments, electronicdevice 10 includes a single attached semiconductor package, while otherembodiments call for multiple interconnected packages. By combining oneor more semiconductor packages over a single substrate, manufacturerscan incorporate pre-made components into electronic devices and systems.Because the semiconductor packages include sophisticated functionality,electronic devices can be manufactured using cheaper components and ashorter manufacturing process. The resulting devices are less likely tofail and less expensive to manufacture resulting in lower costs forconsumers.

FIG. 2 a illustrates further detail of DIP 24 mounted on PCB 12. DIP 24includes semiconductor die 34 having contact pads 36. Semiconductor die34 includes an active area containing analog or digital circuitsimplemented as active devices, passive devices, conductive layers, anddielectric layers formed within semiconductor die 34 and areelectrically interconnected according to the electrical design of thedie. For example, the circuit may include one or more transistors,diodes, inductors, capacitors, resistors, and other circuit elementsformed within the active area of die 34. Contact pads 36 are made with aconductive material, such as aluminum (Al), copper (Cu), tin (Sn),nickel (Ni), gold (Au), or silver (Ag), and are electrically connectedto the circuit elements formed within die 34. Contact pads 36 are formedby PVD, CVD, electrolytic plating, or electroless plating process.During assembly of DIP 24, semiconductor die 34 is mounted to a carrier38 using a gold-silicon eutectic layer or adhesive material such asthermal epoxy. The package body includes an insulative packagingmaterial such as polymer or ceramic. Conductor leads 40 are connected tocarrier 38 and wire bonds 42 are formed between leads 40 and contactpads 36 of die 34 as a first level packaging. Encapsulant 44 isdeposited over the package for environmental protection by preventingmoisture and particles from entering the package and contaminating die34, contact pads 36, or wire bonds 42. DIP 24 is connected to PCB 12 byinserting leads 40 into holes formed through PCB 12. Solder material 46is flowed around leads 40 and into the holes to physically andelectrically connect DIP 24 to PCB 12. Solder material 46 can be anymetal or electrically conductive material, e.g., Sn, lead (Pb), Au, Ag,Cu, zinc (Zn), bismuthinite (Bi), and alloys thereof, with an optionalflux material. For example, the solder material can be eutectic Sn/Pb,high-lead, or lead-free.

FIG. 2 b illustrates further detail of BCC 22 mounted on PCB 12.Semiconductor die 47 is connected to a carrier by wire bond style firstlevel packaging. BCC 22 is mounted to PCB 12 with a BCC style secondlevel packaging. Semiconductor die 47 having contact pads 48 is mountedover a carrier using an underfill or epoxy-resin adhesive material 50.Semiconductor die 47 includes an active area containing analog ordigital circuits implemented as active devices, passive devices,conductive layers, and dielectric layers formed within semiconductor die47 and are electrically interconnected according to the electricaldesign of the die. For example, the circuit may include one or moretransistors, diodes, inductors, capacitors, resistors, and other circuitelements formed within the active area of die 47. Contact pads 48 aremade with a conductive material, such as Al, Cu, Sn, Ni, Au, or Ag, andare electrically connected to the circuit elements formed within die 47.Contact pads 48 are formed by PVD, CVD, electrolytic plating, orelectroless plating process. Wire bonds 54 and bond pads 56 and 58electrically connect contact pads 48 of semiconductor die 47 to contactpads 52 of BCC 22 forming the first level packaging. Molding compound orencapsulant 60 is deposited over semiconductor die 47, wire bonds 54,contact pads 48, and contact pads 52 to provide physical support andelectrical isolation for the device. Contact pads 64 are formed on asurface of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess and are typically plated to prevent oxidation. Contact pads 64electrically connect to one or more conductive signal traces 14. Soldermaterial is deposited between contact pads 52 of BCC 22 and contact pads64 of PCB 12. The solder material is reflowed to form bumps 66, whichform a mechanical and electrical connection between BCC 22 and PCB 12.

In FIG. 2 c, semiconductor die 18 is mounted face down to carrier 76with a flip chip style first level packaging. BGA 20 is attached to PCB12 with a BGA style second level packaging. Active area 70 containinganalog or digital circuits implemented as active devices, passivedevices, conductive layers, and dielectric layers formed withinsemiconductor die 18 is electrically interconnected according to theelectrical design of the die. For example, the circuit may include oneor more transistors, diodes, inductors, capacitors, resistors, and othercircuit elements formed within active area 70 of semiconductor die 18.Semiconductor die 18 is electrically and mechanically attached tocarrier 76 through a large number of individual conductive solder bumpsor balls 78. Solder bumps 78 are formed on bump pads or interconnectsites 80, which are disposed on active areas 70. Bump pads 80 are madewith a conductive material, such as Al, Cu, Sn, Ni, Au, or Ag, and areelectrically connected to the circuit elements formed in active area 70.Bump pads 80 are formed by PVD, CVD, electrolytic plating, orelectroless plating process. Solder bumps 78 are electrically andmechanically connected to contact pads or interconnect sites 82 oncarrier 76 by a solder reflow process.

BGA 20 is electrically and mechanically attached to PCB 12 by a largenumber of individual conductive solder bumps or balls 86. The solderbumps are formed on bump pads or interconnect sites 84. The bump pads 84are electrically connected to interconnect sites 82 through conductivelines 90 routed through carrier 76. Contact pads 88 are formed on asurface of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess and are typically plated to prevent oxidation. Contact pads 88electrically connect to one or more conductive signal traces 14. Thesolder bumps 86 are electrically and mechanically connected to contactpads or bonding pads 88 on PCB 12 by a solder reflow process. Moldingcompound or encapsulant 92 is deposited over semiconductor die 18 andcarrier 76 to provide physical support and electrical isolation for thedevice. The flip chip semiconductor device provides a short electricalconduction path from the active devices on semiconductor die 18 toconduction tracks on PCB 12 in order to reduce signal propagationdistance, lower capacitance, and achieve overall better circuitperformance. In another embodiment, the semiconductor die 18 can bemechanically and electrically attached directly to PCB 12 using flipchip style first level packaging without carrier 76.

FIGS. 3 a-3 g illustrate a method of forming semiconductor device 100providing a three-dimensional (3D) interposer package having a pluralityof through-silicon via (TSV) die. Turning to FIG. 3 a, dies 102, 104 and106 are mounted to carrier 108. Carrier 108 includes a stiff materialsuch as a glass wafer, Si, ceramic, quartz, or flexible tape substrate.Dies 102, 104 and 106 may include semiconductor devices, or otherelectronic chips or ICs and provide various functions such as memory,controller, ASICs, processor, microcontroller, or combinations thereof.In one embodiment, die 102 includes active ICs, while dies 104 and 106represent ‘dummy’ or non-functional semiconductor dies havingpre-fabricated TSVs. Dies 102, 104 and 106 may be attached to substrate108 using an adhesive that includes an underfill or epoxy polymermaterial. Contact pads 110 are formed over a surface of die 102 using aconductive material, such as Al, Cu, Sn, Ni, Au, or Ag, and areelectrically connected to the circuit elements formed within die 102.Contact pads 110 are formed by PVD, CVD, electrolytic plating, orelectroless plating processes, for example. Vias are formed in dies 104and 106 using deep reactive ion etching (DRIE), laser drilling, wetchemical etch, or another etching process. Insulation 112 is depositedinto the vias to form a conformal coating within the vias. Insulation112 is typically made with silicon dioxide (SiO2), but can also be madewith silicon nitride (Si3N4), silicon oxynitride (SiON), tantalumpentoxide (Ta205), zircon (ZrO2), aluminum oxide (Al203), or othermaterial having dielectric insulation properties. The deposition ofinsulation 112 involves PVD, CVD, printing, sintering, or thermaloxidation, for example. A conductive material is deposited into the viasto form through-silicon vias (TSVs) 114. TSVs 114 are formed using anevaporation, electrolytic plating, electroless plating, screen printing,PVD, or another suitable metal deposition process and include Al, Cu,Sn, Ni, Au, or Ag or another conductive material. In the presentembodiment, TSVs 114 are formed before dies 104 and 106 are mounted tosubstrate 108 in a separate manufacturing process. An optionalinsulation or passivation layer 116 is formed over a surface of dies 104and 106. Insulation layer 116 may be formed before or after TSVs 114.

Turning to FIG. 3 b, molding compound 118 is deposited over device 100to provide electrical isolation and physical support. Molding compound118 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 108 is removed and device 100 is inverted.

Turning to FIG. 3 c, a redistribution layer (RDL) is formed over device100. The RDL operates as a conductive network to route electricalsignals to various areas of the package, including active and passivecircuits of the various semiconductor die, and provides variouselectrical interconnect options during package integration. Passivationlayer 120 is deposited and patterned over dies 102, 104 and 106 and mayinclude an insulation material such as polyimide, benzocyclobutene(BCB), polybenzoxazoles (PBO), epoxy based insulating polymer, or otherinsulating materials. Passivation layer 120 is patterned to expose TSVs114 of dies 104 and 106 and contact pads 110 of die 102. Metal layer 122is deposited and patterned over passivation layer 120. Metal layer 122may include multiple layers of conductive material and may be formedusing a PVD, CVD, electrolytic plating, or electroless plating process.Passivation layer 124 is formed over metal layer 122. Passivation layer124 is patterned to expose portions of metal layer 122. Metal layer 126is deposited over passivation layer 124. In one embodiment, metal layer126 includes an under-bump metallization (UBM) that is formed over theexposed portions of metal layer 122. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 3 d, device 100 is inverted and molding compound 118 isthinned to expose a backside of die 102 and dies 104 and 106. Moldingcompound 118 may be thinned using a chemical-mechanical planarization(CMP), mechanical backgrinding, plasma etching, wet etch, dry etch oranother thinning process. Carrier 128 is mounted to device 100 toprovide physical support and includes a stiff substrate material.

Turning to FIG. 3 e, an additional RDL structure is formed over device100. Passivation layer 130 includes an insulative material and isdeposited over dies 102, 104 and 106. Passivation layer 130 is patternedto expose TSVs 114 of dies 104 and 106. Metal layer 132 is depositedover passivation layer 130. In one embodiment, metal layer 132 includesa UBM that is formed over TSVs 114. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 3 f, semiconductor package 134 is mounted to device 100using solder bumps 136. Package 134 includes one or more pre-packagedsemiconductor die and includes contact pads for connecting package 134to external systems. Package 134 includes general application integratedcircuits such as filters, memory chips, and processors, for example.Package 134 is connected to device 100 using solder bumps 136. Bumps 136include an electrically conductive material such as solder, Sn, Pb, Au,Ag, Cu, Zn, Bi, and alloys thereof, with an optional flux material. Forexample, the solder material can be eutectic Sn/Pb, high lead, or leadfree. The solder material is deposited between metal layer or UBM 132and the contact pads of package 134. The solder material is thenreflowed to form bumps 136 which form an electrical and mechanicalconnection between package 134 and device 100. In alternativeembodiments, other interconnect structures such as stud bumping,wirebonds or conductive pillars are used to form the connection betweenpackage 134 and device 100.

In one embodiment, as shown in FIG. 3 f, package 134 includes substrateor PCB 138 over which a plurality of semiconductor dies are mounted.Substrate 138 includes contact pads formed over opposing surfaces ofsubstrate 138 and an interconnect structure formed in substrate 138 toconnect the contact pads. The semiconductor dies are mounted oversubstrate 138 using die attach adhesive. The dies are electricallyconnected to one another and substrate 138 using a plurality ofwirebonds. A molding or encapsulant material is deposited over the diesand substrate 138 to provide electrical isolation and mechanicalprotection for package 134. In alternative embodiments, however, package134 includes any combination of semiconductor dies and other componentsto provide the required functionality. In many cases, package 134 ispre-manufactured and tested before being integrated into device 100.After mounting package 134, carrier 128 may be removed.

Turning to FIG. 3 g, an optional interconnect structure is connected todevice 100. The interconnect structure includes solder bumps 140deposited over insulation layer 124 and electrically connected to metallayer 126. Bumps 140 include an electrically conductive material such assolder. The conductive material is deposited over the patterned regionsof insulation layer 124 and is reflowed to form bumps 140. Inalternative embodiments, other interconnect structures such as studbumps, microbumps, pillar bumps, wirebonds, conductive pillars, or othermetal connection structures using Cu, Au, or Ni, for example, areconnected to semiconductor device 100 to allow for the connection ofexternal system components.

As shown in FIG. 3 g, device 100 is singulated and mounted to PCB orsubstrate 142. Contact pads 144 are formed over a surface of substrate142 and include a conductive material. Bumps 140 are mounted to contactpads 144 and are reflowed to form an electrical and mechanicalconnection between device 100 and substrate 142.

Using this method, a semiconductor device including a 3D interposerpackage is manufactured. The device includes dummy dies having TSVs forforming electrical connections between circuits formed over a firstsurface of the device and circuits formed over a second surface of thedevice. Accordingly, the semiconductor device enables the formation of3D packages for use in package-on-package (POP) and flip chipapplications. Also, because dummy dies are used, the TSVs are formed inthe dies before they are integrated into the final package. Accordingly,the manufacturing process is simplified, improving device yield.

FIG. 4 illustrates a top view of a wafer having a plurality of dummydies having TSVs for use in semiconductor device 100. Wafer 150 includesa Si substrate or other material suitable for the formation ofsemiconductor devices. A plurality of dies are formed over wafer 150. Asshown on FIG. 4, die 152 includes alignment markings 154 to facilitateplacement of dummy die 152 over substrate 108 when manufacturingsemiconductor device 100. TSVs 156 are pre-manufactured within die 152during die fabrication.

FIGS. 5 a-5 g illustrate a method of forming semiconductor device 200providing a 3D interposer package having a plurality of TSV die, an RDLstructure is formed over both sides of substrate 208. Turning to FIG. 5a, dies 202, 204 and 206 are mounted to carrier 208. Carrier 208includes a stiff material such as a glass wafer, Si, ceramic, quartz, orflexible tape substrate. In one embodiment, die 202 includes active ICs,while dies 204 and 206 represent ‘dummy’ or non-functional semiconductordies having pre-fabricated TSVs. Contact pads 210 are formed over asurface of die 202 using a conductive material, such as Al, Cu, Sn, Ni,Au, or Ag, and are electrically connected to the circuit elements formedwithin die 202. Contact pads 210 are formed by PVD, CVD, electrolyticplating, or electroless plating processes, for example. Vias are formedin dies 204 and 206 using DRIE, laser drilling, or another etchingprocess. Insulation 212 is deposited into the vias to form a conformalcoating within the vias. Insulation 212 is typically made with SiO2, butcan also be made with Si3N4, SiON, Ta205, ZrO2, Al203, or other materialhaving dielectric insulation properties. A conductive material isdeposited into the vias to form TSVs 214. TSVs 214 are formed using anevaporation, electrolytic plating, electroless plating, screen printing,PVD, or another suitable metal deposition process and include Al, Cu,Sn, Ni, Au, or Ag or another conductive material. In the presentembodiment, TSVs 214 are formed before dies 204 and 206 are mounted tosubstrate 208 in a separate manufacturing process. An optionalinsulation or passivation layer 216 is formed over a surface of dies 204and 206. Insulation layer 216 may be formed before or after TSVs 214.

Turning to FIG. 5 b, molding compound 218 is deposited over device 200to provide electrical isolation and physical support. Molding compound218 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 208 is removed and device 200 is inverted.

Turning to FIG. 5 c, an RDL is formed over device 200. The RDL operatesas a conductive network to route electrical signals to various areas ofthe package, including active and passive circuits of the varioussemiconductor die, and provides various electrical interconnect optionsduring package integration. Passivation layer 220 is deposited andpatterned over dies 202, 204 and 206 and may include an insulationmaterial such as polyimide, BCB, PBO, epoxy based insulating polymer, orother insulating materials. Passivation layer 220 is patterned to exposeTSVs 214 of dies 204 and 206 and contact pads 210 of die 202. Metallayer 222 is deposited and patterned over passivation layer 220. Metallayer 222 may include multiple layers of conductive material and may beformed using a PVD, CVD, electrolytic plating, or electroless platingprocess. Passivation layer 224 is formed over metal layer 222.Passivation layer 224 is patterned to expose portions of metal layer222. Metal layer 226 is deposited over passivation layer 224. In oneembodiment, metal layer 226 includes a UBM that is formed over theexposed portions of metal layer 222. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 5 d, device 200 is inverted and molding compound 218 isthinned to expose a backside of die 202 and dies 204 and 206. Moldingcompound 218 may be thinned using a CMP, mechanical backgrinding, plasmaetching, wet etch, dry etch or another thinning process. Carrier 228 ismounted to device 200 to provide physical support and includes a stiffsubstrate material.

Turning to FIG. 5 e, an additional RDL structure is formed over device200. Passivation layer 229 includes an insulative material and isdeposited over dies 202, 204 and 206. Passivation layer 229 is patternedto expose TSVs 214 of dies 204 and 206. Metal layer 231 is depositedover passivation layer 229 and forms an electrical connection with TSVs214 of dies 204 and 206. Passivation layer 230 includes an insulativematerial and is deposited over metal layer 231. Passivation layer 230 ispatterned to expose portions of metal layer 231. Metal layer 232 isdeposited over passivation layer 230. In one embodiment, metal layer 232includes a UBM that is formed over TSVs 214. In one embodiment, the UBMincludes a wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 5 f, semiconductor package 234 is mounted to device 200using solder bumps 236. Package 234 includes one or more pre-packagedsemiconductor die and includes contact pads for connecting package 234to external systems. Package 234 includes general application integratedcircuits such as filters, memory chips, and processors, for example.Package 234 is connected to device 200 using solder bumps 236. Bumps 236include an electrically conductive material such as solder, Sn, Pb, Au,Ag, Cu, Zn, Bi, and alloys thereof, with an optional flux material. Forexample, the solder material can be eutectic Sn/Pb, high lead, or leadfree. The solder material is deposited between metal layer or UBM 232and the contact pads of package 234. The solder material is thenreflowed to form bumps 236 which form an electrical and mechanicalconnection between package 234 and device 200. In alternativeembodiments, other interconnect structures such as stud bumping,wirebonds or conductive pillars are used to form the connection betweenpackage 234 and device 200.

In one embodiment, as shown in FIG. 5 f, package 234 includes substrateor PCB 238 over which a plurality of semiconductor dies are mounted.Substrate 238 includes contact pads formed over opposing surfaces ofsubstrate 238 and an interconnect structure formed in substrate 238 toconnect the contact pads. The semiconductor dies are mounted oversubstrate 238 using die attach adhesive. The dies are electricallyconnected to one another and substrate 238 using a plurality ofwirebonds. A molding or encapsulant material is deposited over the diesand substrate 238 to provide electrical isolation and mechanicalprotection for package 234. In alternative embodiments, however, package234 includes any combination of semiconductor dies and other componentsto provide the required functionality. In many cases, package 234 ispre-manufactured and tested before being integrated into device 200.After mounting package 234, carrier 228 may be removed.

Turning to FIG. 5 g, an optional interconnect structure is connected todevice 200. The interconnect structure includes solder bumps 240deposited over insulation layer 224 and electrically connected to metallayer 226. Bumps 240 include an electrically conductive material such assolder. The conductive material is deposited over the patterned regionsof insulation layer 224 and is reflowed to form bumps 240. Inalternative embodiments, other interconnect structures such as studbumps, microbumps, pillar bumps, wirebonds, conductive pillars, or othermetal connection structures using Cu, Au, or Ni, for example, areconnected to semiconductor device 200 to allow for the connection ofexternal system components.

As shown in FIG. 5 g, device 200 is mounted to PCB or substrate 242.Contact pads 244 are formed over a surface of substrate 242 and includea conductive material. Bumps 240 are mounted to contact pads 244 and arereflowed to form an electrical and mechanical connection between device200 and substrate 242.

FIGS. 6 a-6 g illustrate a method of forming semiconductor device 300providing a 3D interposer package having a plurality of TSV die, a dieis flip-chip mounted to semiconductor device 300. Turning to FIG. 6 a,dies 302, 304 and 306 are mounted to carrier 308. Carrier 308 includes astiff material such as a glass wafer, Si, ceramic, quartz, or flexibletape substrate. In one embodiment, die 302 includes active ICs, whiledies 304 and 306 represent ‘dummy’ or non-functional semiconductor dieshaving pre-fabricated TSVs. Contact pads 310 are formed over a surfaceof die 302 using a conductive material, such as Al, Cu, Sn, Ni, Au, orAg, and are electrically connected to the circuit elements formed withindie 302. Contact pads 310 are formed by PVD, CVD, electrolytic plating,or electroless plating processes, for example. Vias are formed in dies304 and 306 using DRIE, laser drilling, or another etching process.Insulation 312 is deposited into the vias to form a conformal coatingwithin the vias. Insulation 312 is typically made with SiO2, but canalso be made with Si3N4, SiON, Ta205, ZrO2, Al203, or other materialhaving dielectric insulation properties. A conductive material isdeposited into the vias to form TSVs 314. TSVs 314 are formed using anevaporation, electrolytic plating, electroless plating, screen printing,PVD, or another suitable metal deposition process and include Al, Cu,Sn, Ni, Au, or Ag or another conductive material. In the presentembodiment, TSVs 314 are formed before dies 304 and 306 are mounted tosubstrate 308 in a separate manufacturing process. An optionalinsulation or passivation layer 316 is formed over a surface of dies 304and 306. Insulation layer 316 may be formed before or after TSVs 314.

Turning to FIG. 6 b, molding compound 318 is deposited over device 300to provide electrical isolation and physical support. Molding compound318 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 308 is removed and device 300 is inverted.

Turning to FIG. 6 c, an RDL is formed over device 300. The RDL operatesas a conductive network to route electrical signals to various areas ofthe package, including active and passive circuits of the varioussemiconductor die, and provides various electrical interconnect optionsduring package integration. Passivation layer 320 is deposited andpatterned over dies 302, 304 and 306 and may include an insulationmaterial such as polyimide, BCB, PBO, epoxy based insulating polymer, orother insulating materials. Passivation layer 320 is patterned to exposeTSVs 314 of dies 304 and 306 and contact pads 310 of die 302. Metallayer 322 is deposited and patterned over passivation layer 320. Metallayer 322 may include multiple layers of conductive material and may beformed using a PVD, CVD, electrolytic plating, or electroless platingprocess. Passivation layer 324 is formed over metal layer 322.Passivation layer 324 is patterned to expose portions of metal layer322. Metal layer 326 is deposited over passivation layer 324. In oneembodiment, metal layer 326 includes a UBM that is formed over theexposed portions of metal layer 322. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 6 d, device 300 is inverted and molding compound 318 isthinned to expose a backside of die 302 and dies 304 and 306. Moldingcompound 318 may be thinned using a CMP, mechanical backgrinding, plasmaetching, wet etch, dry etch or another thinning process. Carrier 328 ismounted to device 300 to provide physical support and includes a stiffsubstrate material.

Turning to FIG. 6 e, an additional RDL structure is formed over device300. Passivation layer 330 includes an insulative material and isdeposited over dies 302, 304 and 306. Passivation layer 330 is patternedto expose TSVs 314 of dies 304 and 306. Metal layer 332 is depositedover passivation layer 330. In one embodiment, metal layer 332 includesa UBM that is formed over TSVs 314. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Die 334 is mounted to device 300 using solder bumps 336. Die 334includes contact pads 335 formed over a surface of die 334 using aconductive material, such as Al, Cu, Sn, Ni, Au, or Ag. Contact pads 335are formed by PVD, CVD, electrolytic plating, or electroless platingprocesses, for example. Die 334 includes general application integratedcircuits such as filters, memory, and processors, for example. Die 334is connected to device 300 using solder bumps 336. Bumps 336 include anelectrically conductive material such as solder, Sn, Pb, Au, Ag, Cu, Zn,Bi, and alloys thereof, with an optional flux material. For example, thesolder material can be eutectic Sn/Pb, high lead, or lead free. Thesolder material is deposited between metal layer or UBM 332 and contactpads 335 of die 334. The solder material is then reflowed to form bumps336 which form an electrical and mechanical connection between die 334and device 300. In alternative embodiments, other interconnectstructures such as stud bumping, wirebonds or conductive pillars areused to form the connection between die 334 and device 300.

Turning to FIG. 6 f, molding compound 338 is deposited over die 334 toprovide electrical isolation and mechanical protection. Molding compound338 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 328 is removed and device 300 is inverted.

Turning to FIG. 6 g, an optional interconnect structure is connected todevice 300. The interconnect structure includes solder bumps 340deposited over insulation layer 324 and electrically connected to metallayer 326. Bumps 340 include an electrically conductive material such assolder. The conductive material is deposited over the patterned regionsof insulation layer 324 and is reflowed to form bumps 340. Inalternative embodiments, other interconnect structures such as studbumps, microbumps, pillar bumps, wirebonds, conductive pillars, or othermetal connection structures using Cu, Au, or Ni, for example, areconnected to semiconductor device 300 to allow for the connection ofexternal system components.

As shown in FIG. 6 g, device 300 is mounted to PCB or substrate 342.Contact pads 344 are formed over a surface of substrate 342 and includea conductive material. Bumps 340 are mounted to contact pads 344 and arereflowed to form an electrical and mechanical connection between device300 and substrate 342.

FIG. 7 illustrates semiconductor device 300 providing a 3D interposerpackage having a plurality of TSV die, a die is flip-chip mounted tosemiconductor device 300 using an underfill material. Semiconductordevice 300 includes dies 302, 304 and 306. Dies 304 and 306 includepre-fabricated TSVs 314. An RDL structure is formed over first andsecond surfaces of semiconductor device 300. Die 334 is mounted tosemiconductor device 300 using bumps 336. An optional underfill material337 is deposited between die 334 and passivation layer 330. In oneembodiment, capillary action causes underfill 337 to flow between die334 and passivation layer 330 to form a physical bond between die 334and passivation layer 330.

FIGS. 8 a-8 i illustrate a method of forming semiconductor device 400providing a 3D interposer package having stacked TSV die, a die isflip-chip mounted to semiconductor device 400. Turning to FIG. 8 a, dies402, 404 and 406 are mounted to carrier 408. Carrier 408 includes astiff material such as a glass wafer, Si, ceramic, quartz, or flexibletape substrate. In one embodiment, die 402 includes active ICs, whiledies 404 and 406 represent ‘dummy’ or non-functional semiconductor dieshaving pre-fabricated TSVs. Contact pads 410 are formed over a surfaceof die 402 using a conductive material, such as Al, Cu, Sn, Ni, Au, orAg, and are electrically connected to the circuit elements formed withindie 402. Contact pads 410 are formed by PVD, CVD, electrolytic plating,or electroless plating processes, for example. Vias are formed in dies404 and 406 using DRIE, laser drilling, or another etching process.Insulation 412 is deposited into the vias to form a conformal coatingwithin the vias. A conductive material is deposited into the vias toform TSVs 414. TSVs 414 are formed using an evaporation, electrolyticplating, electroless plating, screen printing, PVD, or another suitablemetal deposition process and include Al, Cu, Sn, Ni, Au, or Ag oranother conductive material. In the present embodiment, TSVs 414 areformed before dies 404 and 406 are mounted to substrate 408 in aseparate manufacturing process. An optional insulation or passivationlayer 416 is formed over a surface of dies 404 and 406. Insulation layer416 may be formed before or after TSVs 414.

Turning to FIG. 8 b, molding compound 418 is deposited over device 400to provide electrical isolation and physical support. Molding compound418 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 408 is removed and device 400 is inverted.

Turning to FIG. 8 c, an RDL is formed over device 400. The RDL operatesas a conductive network to route electrical signals to various areas ofthe package, including active and passive circuits of the varioussemiconductor die, and provides various electrical interconnect optionsduring package integration. Passivation layer 420 is deposited andpatterned over dies 402, 404 and 406 and may include an insulationmaterial such as polyimide, BCB, PBO, epoxy based insulating polymer, orother insulating materials. Passivation layer 420 is patterned to exposeTSVs 414 of dies 404 and 406 and contact pads 410 of die 402. Metallayer 422 is deposited and patterned over passivation layer 420. Metallayer 422 may include multiple layers of conductive material and may beformed using a PVD, CVD, electrolytic plating, or electroless platingprocess. Passivation layer 424 is formed over metal layer 422.Passivation layer 424 is patterned to expose portions of metal layer422. Metal layer 426 is deposited over passivation layer 424. In oneembodiment, metal layer 426 includes a UBM that is formed over theexposed portions of metal layer 422. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 8 d, device 400 is inverted and molding compound 418 isthinned to expose a backside of die 402 and dies 404 and 406. Moldingcompound 418 may be thinned using a CMP, mechanical backgrinding, plasmaetching, wet etch, dry etch or another thinning process. Carrier 428 ismounted to device 400 to provide physical support and includes a stiffsubstrate material.

Turning to FIG. 8 e, a second level of device die and dummy TSV die ismounted to semiconductor device 400. TSVs 430 are formed in die 402. Inother embodiments, TSVs 430 may be formed in die 402 at any time duringthe fabrication process. In one embodiment, for example, TSVs 430 areformed in die 402 before it is mounted to substrate 408. An optionalinsulation layer 432 is formed around a perimeter of TSVs 430. Aconductive material is deposited into vias formed in die 402 to formTSVs 430. A top portion of TSVs 430 forms a contact pad that is used tointerconnect die 402 with other system components. Die 434 havingcontact pads 436 is mounted to die 402 using bumps 438. Bumps 438include a conductive material and form an electrical and mechanicalconnection between dies 402 and 434. In alternative embodiments,conductive adhesives, or other connection mechanisms are used to connectdies 402 and 434.

Dies 440 and 442 are mounted to semiconductor device 400. Vias areformed in dies 440 and 442 using DRIE, laser drilling, or anotheretching process. Insulation 446 is deposited into the vias to form aconformal coating within the vias. A conductive material is depositedinto the vias to form TSVs 444. TSVs 444 are formed using anevaporation, electrolytic plating, electroless plating, screen printing,PVD, or another suitable metal deposition process and include Al, Cu,Sn, Ni, Au, or Ag or another conductive material. In the presentembodiment, TSVs 444 are formed before dies 440 and 442 are mounted todevice 400. An optional insulation or passivation layer 448 is formedover a surface of dies 440 and 442. Insulation layer 448 may be formedbefore or after TSVs 444. Contact pads 450 are formed over a surface ofdies 440 and 442 in electrical contact with TSVs 444. Dies 440 and 442are mounted to dies 402 and 404 using bumps 452. Bumps 452 include aconductive material and form an electrical and mechanical connectionbetween dies 440 and 442 and dies 402 and 404. In alternativeembodiments, conductive adhesives, or other connection mechanisms areused to connect dies 440 and 442 and dies 402 and 404.

Turning to FIG. 8 f, molding compound 454 is deposited over device 400to provide electrical insulation and mechanical protection to die 434and dies 440 and 442. Molding compound 454 includes epoxy acrylate orother polymer material and is applied by transfer molding, liquidencapsulant molding, or other molding processes. An additional RDLstructure is formed over device 400. Molding compound 454 is thinned toexpose dies 434, 440 and 442. Passivation layer 456 includes aninsulative material and is deposited over dies 434, 440 and 442.Passivation layer 456 is patterned to expose TSVs 444 of dies 440 and442. Metal layer 458 is deposited over passivation layer 456 andelectrically connected to TSVs 444. In one embodiment, metal layer 458includes a UBM that is formed over TSVs 444. In one embodiment, the UBMincludes a wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 8 g, die 460 is flip-chip mounted to device 400 usingsolder bumps 464. Die 460 includes contact pads 462 formed over asurface of die 460 using a conductive material, such as Al, Cu, Sn, Ni,Au, or Ag. Contact pads 462 are formed by PVD, CVD, electrolyticplating, or electroless plating processes, for example. Die 460 includesgeneral application integrated circuits such as filters, memory, andprocessors, for example. Bumps 464 include an electrically conductivematerial such as solder, Sn, Pb, Au, Ag, Cu, Zn, Bi, and alloys thereof,with an optional flux material. For example, the solder material can beeutectic Sn/Pb, high lead, or lead free. The solder material isdeposited between metal layer or UBM 458 and contact pads 462 of die460. The solder material is then reflowed to form bumps 464 which forman electrical and mechanical connection between die 460 and device 400.In alternative embodiments, other interconnect structures such as studbumping, wirebonds or conductive pillars are used to form the connectionbetween die 460 and device 400. An optional underfill material 466 isdeposited between die 460 and passivation layer 456. In one embodiment,capillary action causes underfill 466 to flow between die 460 andpassivation layer 456 to form a physical bond between die 460 andpassivation layer 456.

Turning to FIG. 8 h, device 400 is placed in mechanical clamp 468 andcarrier 428 is removed. An optional interconnect structure is connectedto device 400. The interconnect structure includes solder bumps 470deposited over insulation layer 424 and electrically connected to metallayer 426. Bumps 470 include an electrically conductive material such assolder. The conductive material is deposited over the patterned regionsof insulation layer 424 and is reflowed to form bumps 470. Inalternative embodiments, other interconnect structures such as studbumps, microbumps, pillar bumps, wirebonds, conductive pillars, or othermetal connection structures using Cu, Au, or Ni, for example, areconnected to semiconductor device 400 to allow for the connection ofexternal system components.

Turning to FIG. 8 i, device 400 is removed from clamp 468 and mounted toPCB or substrate 472. Contact pads 474 are formed over a surface ofsubstrate 472 and include a conductive material. Bumps 470 are mountedto contact pads 474 and are reflowed to form an electrical andmechanical connection between device 400 and substrate 472.

FIGS. 9 a-9 i illustrate a method of forming semiconductor device 500providing a 3D interposer package having stacked TSV die, asemiconductor package is mounted to semiconductor device 500. Turning toFIG. 9 a, dies 502, 504 and 506 are mounted to carrier 508. Carrier 508includes a stiff material such as a glass wafer, Si, ceramic, quartz, orflexible tape substrate. In one embodiment, die 502 includes active ICs,while dies 504 and 506 represent ‘dummy’ or non-functional semiconductordies having pre-fabricated TSVs. Contact pads 510 are formed over asurface of die 502 using a conductive material, such as Al, Cu, Sn, Ni,Au, or Ag, and are electrically connected to the circuit elements formedwithin die 502. Contact pads 510 are formed by PVD, CVD, electrolyticplating, or electroless plating processes, for example. Vias are formedin dies 504 and 506 using DRIE, laser drilling, or another etchingprocess. Insulation 512 is deposited into the vias to form a conformalcoating within the vias. A conductive material is deposited into thevias to form TSVs 514. TSVs 514 are formed using an evaporation,electrolytic plating, electroless plating, screen printing, PVD, oranother suitable metal deposition process and include Al, Cu, Sn, Ni,Au, or Ag or another conductive material. In the present embodiment,TSVs 514 are formed before dies 504 and 506 are mounted to substrate 508in a separate manufacturing process. An optional insulation orpassivation layer 516 is formed over a surface of dies 504 and 506.Insulation layer 516 may be formed before or after TSVs 514.

Turning to FIG. 9 b, molding compound 518 is deposited over device 500to provide electrical isolation and physical support. Molding compound518 includes epoxy acrylate or other polymer material and is applied bytransfer molding, liquid encapsulant molding, or other moldingprocesses. Carrier 508 is removed and device 500 is inverted.

Turning to FIG. 9 c, an RDL is formed over device 500. The RDL operatesas a conductive network to route electrical signals to various areas ofthe package, including active and passive circuits of the varioussemiconductor die, and provides various electrical interconnect optionsduring package integration. Passivation layer 520 is deposited andpatterned over dies 502, 504 and 506 and may include an insulationmaterial such as polyimide, BCB, PBO, epoxy based insulating polymer, orother insulating materials. Passivation layer 520 is patterned to exposeTSVs 514 of dies 504 and 506 and contact pads 510 of die 502. Metallayer 522 is deposited and patterned over passivation layer 520. Metallayer 522 may include multiple layers of conductive material and may beformed using a PVD, CVD, electrolytic plating, or electroless platingprocess. Passivation layer 524 is formed over metal layer 522.Passivation layer 524 is patterned to expose portions of metal layer522. Metal layer 526 is deposited over passivation layer 524. In oneembodiment, metal layer 526 includes a UBM that is formed over theexposed portions of metal layer 522. In one embodiment, the UBM includesa wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 9 d, device 500 is inverted and molding compound 518 isthinned to expose a backside of die 502 and dies 504 and 506. Moldingcompound 518 may be thinned using a CMP, mechanical backgrinding, plasmaetching, wet etch, dry etch or another thinning process. Carrier 528 ismounted to device 500 to provide physical support and includes a stiffsubstrate material.

Turning to FIG. 9 e, a second level of device die and dummy TSV die ismounted to semiconductor device 500. TSVs 530 are formed in die 502. Inother embodiments, TSVs 530 may be formed in die 502 at any time duringthe fabrication process. In one embodiment, for example, TSVs 530 areformed in die 502 before it is mounted to substrate 508. An optionalinsulation layer 532 is formed around a perimeter of TSVs 530. Aconductive material is deposited into vias formed in die 502 to formTSVs 530. A top portion of TSVs 530 forms a contact pad that is used tointerconnect die 502 with other system components. Die 534 havingcontact pads 536 is mounted to die 502 using bumps 538. Bumps 538include a conductive material and form an electrical and mechanicalconnection between dies 502 and 534. In alternative embodiments,conductive adhesives, or other connection mechanisms are used to connectdies 502 and 534.

Dies 540 and 542 are mounted to semiconductor device 500. Vias areformed in dies 540 and 542 using DRIE, laser drilling, or anotheretching process. Insulation 546 is deposited into the vias to form aconformal coating within the vias. A conductive material is depositedinto the vias to form TSVs 544. TSVs 544 are formed using anevaporation, electrolytic plating, electroless plating, screen printing,PVD, or another suitable metal deposition process and include Al, Cu,Sn, Ni, Au, or Ag or another conductive material. In the presentembodiment, TSVs 544 are formed before dies 540 and 542 are mounted todevice 500. An optional insulation or passivation layer 548 is formedover a surface of dies 540 and 542. Insulation layer 548 may be formedbefore or after TSVs 544. Contact pads 550 are formed over a surface ofdies 540 and 542 in electrical contact with TSVs 544. Dies 540 and 542are mounted to dies 502 and 504 using bumps 552. Bumps 552 include aconductive material and form an electrical and mechanical connectionbetween dies 540 and 542 and dies 502 and 504. In alternativeembodiments, conductive adhesives, or other connection mechanisms areused to connect dies 540 and 542 and dies 502 and 504.

Turning to FIG. 9 f, molding compound 554 is deposited over device 500to provide electrical insulation and mechanical protection to die 534and dies 540 and 542. Molding compound 554 includes epoxy acrylate orother polymer material and is applied by transfer molding, liquidencapsulant molding, or other molding processes. An additional RDLstructure is formed over device 500. Molding compound 554 is thinned toexpose dies 534, 540 and 542. Passivation layer 556 includes aninsulative material and is deposited over dies 534, 540 and 542.Passivation layer 556 is patterned to expose TSVs 544 of dies 540 and542. Metal layer 558 is deposited over passivation layer 556 andelectrically connected to TSVs 544. In one embodiment, metal layer 558includes a UBM that is formed over TSVs 544. In one embodiment, the UBMincludes a wetting layer, barrier layer, and adhesive layer.

Turning to FIG. 9 g, semiconductor package 560 is mounted to device 500using solder bumps 562. Package 560 includes one or more pre-packagedsemiconductor die and includes contact pads for connecting package 560to external systems. Package 560 includes general application integratedcircuits such as filters, memory chips, and processors, for example.Package 560 is connected to device 500 using solder bumps 562. Bumps 562include an electrically conductive material such as solder, Sn, Pb, Au,Ag, Cu, Zn, Bi, and alloys thereof, with an optional flux material. Forexample, the solder material can be eutectic Sn/Pb, high lead, or leadfree. The solder material is deposited between metal layer or UBM 558and the contact pads of package 560. The solder material is thenreflowed to form bumps 562 which form an electrical and mechanicalconnection between package 560 and device 500. In alternativeembodiments, other interconnect structures such as stud bumping,wirebonds or conductive pillars are used to form the connection betweenpackage 560 and device 500.

In one embodiment, as shown in FIG. 9 g, package 560 includes substrateor PCB 564 over which a plurality of semiconductor dies are mounted. PCB564 includes contact pads formed over opposing surfaces of PCB 564 andan interconnect structure formed in PCB 564 to connect the contact pads.The semiconductor dies are mounted over PCB 564 using die attachadhesive. The dies are electrically connected to one another and PCB 564using a plurality of wirebonds. A molding or encapsulant material isdeposited over the dies and PCB 564 to provide electrical isolation andmechanical protection for package 560. In alternative embodiments,however, package 560 includes any combination of semiconductor dies andother components to provide the required functionality. In many cases,package 560 is pre-manufactured and tested before being integrated intodevice 500.

Turning to FIG. 9 h, carrier 528 may be removed and an optionalinterconnect structure is connected to semiconductor device 500. Theinterconnect structure includes solder bumps 566 deposited overinsulation layer 524 and electrically connected to metal layer 526.Bumps 566 include an electrically conductive material such as solder.The conductive material is deposited over the patterned regions ofinsulation layer 524 and is reflowed to form bumps 566. In alternativeembodiments, other interconnect structures such as stud bumps,microbumps, pillar bumps, wirebonds, conductive pillars, or other metalconnection structures using Cu, Au, or Ni, for example, are connected tosemiconductor device 500 to allow for the connection of external systemcomponents.

Turning to FIG. 9 i, device 500 is mounted to PCB or substrate 568.Contact pads 570 are formed over a surface of substrate 568 and includea conductive material. Bumps 566 are mounted to contact pads 570 and arereflowed to form an electrical and mechanical connection between device500 and substrate 568.

While one or more embodiments of the present invention have beenillustrated in detail, the skilled artisan will appreciate thatmodifications and adaptations to those embodiments may be made withoutdeparting from the scope of the present invention as set forth in thefollowing claims.

1. A method of making a semiconductor device, comprising: providing acarrier for supporting the semiconductor device; mounting a firstsemiconductor die over the carrier; mounting a first dummy die having afirst through-silicon via (TSV) over the carrier; encapsulating thefirst semiconductor die and the first dummy die using a wafer moldingmaterial; removing the carrier; forming a first redistribution layer(RDL) over a first surface of the first semiconductor die and a firstsurface of the first dummy die to electrically connect the first TSV anda contact pad of the first semiconductor die; forming an insulationlayer over the first RDL; forming a second RDL over a second surface ofthe first dummy die opposite the first surface of the first dummy dieand electrically connected to the first TSV; and connecting asemiconductor package to the second RDL.
 2. The method of claim 1,including: forming a second TSV in the first semiconductor die; mountinga second semiconductor die over the first semiconductor die to connectto the second TSV; and mounting a second dummy die over the first dummydie to connect to the first TSV.
 3. The method of claim 1, includingconnecting the second RDL to a printed circuit board (PCB).
 4. Themethod of claim 1, wherein connecting the semiconductor package to thesecond RDL includes flip-chip mounting a second semiconductor die to thesecond RDL.
 5. The method of claim 4, including thinning the wafermolding material to expose the second surface of the first dummy die anda second surface of the first semiconductor die opposite the firstsurface of the first semiconductor die.
 6. The method of claim 1,wherein the second RDL connects to a plurality of bumps.
 7. The methodof claim 1, wherein the first dummy die includes alignment markings tocontrol placement of the first dummy die over the carrier.
 8. A methodof making a semiconductor device, comprising: providing a temporarycarrier; mounting a first semiconductor die over the temporary carrier;mounting a first dummy die having a first through-silicon via (TSV) overthe temporary carrier; depositing encapsulant over the firstsemiconductor die and the first dummy die; forming a first conductivelayer electrically connected to the first semiconductor die and firstTSV; and forming a second conductive layer electrically connected to thefirst TSV.
 9. The method of claim 8, including connecting asemiconductor package to the second conductive layer.
 10. The method ofclaim 9, wherein connecting the semiconductor package to the secondconductive layer includes flip-chip mounting a second semiconductor dieto the second conductive layer.
 11. The method of claim 8, including:forming a second TSV in the first semiconductor die; mounting a secondsemiconductor die over the first semiconductor die to connect to thesecond TSV; and mounting a second dummy die over the first dummy die toconnect to the first TSV.
 12. The method of claim 8, including thinningthe encapsulant to expose a surface of the first semiconductor die and asurface of the first dummy die.
 13. The method of claim 8, furtherincluding forming a plurality of bumps over the second conductive layer.14. The method of claim 8, wherein the first dummy die includesalignment markings to control placement of the first dummy die over thetemporary carrier.
 15. The method of claim 8, including connecting thesecond conductive layer to a printed circuit board (PCB).
 16. A methodof making a semiconductor device, comprising: providing a carrier;mounting a first semiconductor die over the carrier; mounting a secondsemiconductor die including a conductive via over the carrier; forming afirst conductive layer connected to the first semiconductor die and theconductive via; and forming a second conductive layer connected to theconductive via.
 17. The method of claim 16, wherein the secondsemiconductor die includes alignment markings to control placement ofthe second semiconductor die over the carrier.
 18. The method of claim16, including connecting a semiconductor package to the secondconductive layer.
 19. The method of claim 18, wherein connecting asemiconductor package to the second conductive layer includes flip-chipmounting a third semiconductor die to the second conductive layer. 20.The method of claim 19, including connecting the second conductive layerto a printed circuit board (PCB).
 21. A semiconductor device,comprising: a first semiconductor die; a first dummy die including athrough-silicon via (TSV) that has a first surface coplanar with a firstsurface of the first semiconductor die; encapsulant deposited over thefirst semiconductor die and the first dummy die; a first conductivelayer formed over the first surface of the first semiconductor die andthe first surface of the TSV to electrically connect the firstsemiconductor die and the TSV; and a second conductive layer connectedto a second surface of the TSV opposite the first surface of the TSV.22. The semiconductor device of claim 21, including a semiconductorpackage connected to the second conductive layer.
 23. The semiconductordevice of claim 22, wherein the semiconductor package includes a secondsemiconductor die flip-chip mounted to the second conductive layer. 24.The semiconductor device of claim 21, including: a second semiconductordie mounted over the first semiconductor die and electrically connectedto the first semiconductor die; and a second dummy die mounted over thefirst dummy die and electrically connected to the TSV.
 25. Thesemiconductor device of claim 21, wherein the first dummy die includesalignment markings to control placement of the first dummy die.